Myth Using Synthetic 10W30 Today in GDI Engines ?

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I am in the camp that in a GDI engine that using synthetic 10W30 oil with it's lower NOACK and lower VII's content would be best for a GDI engine (in terms of reducing intake valve depositis) ? Conversely , recent updated tech information may prove such a belief may be a myth and no longer valid : 1) Updated information suggests a lower NOACK oil is not a significant contributor to GDI intake valve deposits . 2) High amounts of VII's are a contributor to intake valve deposits , HOWEVER newer formula VII's are of a composition now to where that is not as much of an issue as with previous earlier SN rated oils and before . Better oil formulas (better base stocks , improved VII's etc.) in SP rated oils suggest that using a good SP rated synthetic D1 / Gen 3 5W30 oil may be best in a GDI engine where both 10W30 and 5W30 were previously recommended in the owner's manual . Lastly , in GDI engines which do not also inclide dual GDI / PFI injectors - it would still be a good practice to runa intaake valve cleaner (i.e. CRC) every 10K miles (or every other OCI along with top tier gas for optimum engine performance ... More capable folks here such as Gokhan , Molekule , etc. can weigh in on key performance indicators for oil / GDI engines I allude to in this post .
 
I'm not a chemical engineer, but I tend to agree with what you are saying to a point. Modern chemistry coming up with these oil add packs is way above my simple degree. I do tend to like a heavier oil for most applications (I'm in Texas) and I like 5w30, 10w30, 5w40, and 10w40.

I'm working on streamlining all my vehicle oil stash and have two weights on hand most of the time. I'm running through a large stash of Kirkland 5w30 and a little bit of Quaker State 5w40. For summer time all vehicles get 10w30 and I may go with that exclusively depending on sales and what's on hand for oil changes at the time.

I do think there is something to lower VII's and to a certain extent lower NOACK can't be a bad either.
 
I am in the camp that in a GDI engine that using synthetic 10W30 oil with it's lower NOACK and lower VII's content would be best for a GDI engine (in terms of reducing intake valve depositis) ? Conversely , recent updated tech information may prove such a belief may be a myth and no longer valid : 1) Updated information suggests a lower NOACK oil is not a significant contributor to GDI intake valve deposits . 2) High amounts of VII's are a contributor to intake valve deposits , HOWEVER newer formula VII's are of a composition now to where that is not as much of an issue as with previous earlier SN rated oils and before . Better oil formulas (better base stocks , improved VII's etc.) in SP rated oils suggest that using a good SP rated synthetic D1 / Gen 3 5W30 oil may be best in a GDI engine where both 10W30 and 5W30 were previously recommended in the owner's manual . Lastly , in GDI engines which do not also inclide dual GDI / PFI injectors - it would still be a good practice to runa intaake valve cleaner (i.e. CRC) every 10K miles (or every other OCI along with top tier gas for optimum engine performance ... More capable folks here such as Gokhan , Molekule , etc. can weigh in on key performance indicators for oil / GDI engines I allude to in this post .


Can you share the source of this information?
 





 








So the source of technical data supporting the statement is a list of threads from BITOG rather than a study, paper, lab experiment, field experience? I was looking forward to reading about this. I guess I zeroed in on the “updated tech information” available. Do we know where the updated tech info is?
 
Thank you. My apologies. I misread that. Nonetheless it would be interesting to read the tech information to support this. We are currently making a no VII limited series of oils. Anything relative to our task at hand would be good to read.

David
He won’t have any. He’ll post that he read it from someone else’s post on here and then he takes it as gospel.
 
Folks - bypassing the word censor, or just using profanity and letting it blank out the vocabulary, is not acceptable. Neither is disparaging another member.

I get the frustration with people asking the same question every month for months on end.

But let’s use “ignore” instead of reverting to profanity or criticism.

This thread stays open because HPL is trying to answer the question and respond to technical discussion.
 
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I am in the camp that in a GDI engine that using synthetic 10W30 oil with it's lower NOACK and lower VII's content would be best for a GDI engine (in terms of reducing intake valve depositis) ? Conversely , recent updated tech information may prove such a belief may be a myth and no longer valid : 1) Updated information suggests a lower NOACK oil is not a significant contributor to GDI intake valve deposits . 2) High amounts of VII's are a contributor to intake valve deposits , HOWEVER newer formula VII's are of a composition now to where that is not as much of an issue as with previous earlier SN rated oils and before . Better oil formulas (better base stocks , improved VII's etc.) in SP rated oils suggest that using a good SP rated synthetic D1 / Gen 3 5W30 oil may be best in a GDI engine where both 10W30 and 5W30 were previously recommended in the owner's manual . Lastly , in GDI engines which do not also inclide dual GDI / PFI injectors - it would still be a good practice to runa intaake valve cleaner (i.e. CRC) every 10K miles (or every other OCI along with top tier gas for optimum engine performance ... More capable folks here such as Gokhan , Molekule , etc. can weigh in on key performance indicators for oil / GDI engines I allude to in this post .
The best way to prevent GDI deposits is by having dual injection. While that apparently wasn't the original reason Toyota was doing it, Ford is now using this as well and I expect we'll see others follow suit.

There are two schools of thought about IVD's:
1. That volatile compounds (so, not VII's) like lighter fractions from the base oil blend, flash off and make their way into the intake tract through the PCV, ultimately forming deposits on the back of the valves.
2. That oil mists produced during operation make their way through the same plumbing and the various components of these mists produce deposits.

The rationale behind focusing on Noack is #1, with #2, you accept that oil will be introduced into the intake regardless and are looking at reducing the concentration of the components that seem most inclined to form deposits.

This strikes me as akin to trying to use 10W-60 to delay rod bearing failure. It's still going to happen, but maybe it happens a bit slower.

One of the biggest drivers of volatilized compounds, and probably the mist angle too, would be fuel dilution, which varies considerably between marques and engine designs. If >5% of your sump is gasoline, clearly, that's going to present as a far greater propensity for volatilized compounds to flash off and get introduced to the intake tract via the PCV.
 
Posted many times, and yet again for new eyes:

My problematic D.I Ford 2.0 ran well this past summer on a RC 10W30, Fuel mileage also improved - though some of that was surely summer gas and shorter warmups. A surprising aspect of note, was that low-speed "lugging" performance was greatly improved over the 5W20. Engine chugged like a locomotive in the top gear(s) around town without protest.

Not generally a big fan of QS 5w-XX synthetic offerings, but this 10W30 FS seemed quite special indeed in-situ. I have a sample sealed in a Nalgene® lab bottle to send off. Curious if the fuel dilution was mitigated, though Blackstone is not a good choice for % fuel data.

- Ken
 
From owners manual for '18 Hyundai Accent .

IMG_4312.JPG
IMG_4314.JPG
 
The best way to prevent GDI deposits is by having dual injection. While that apparently wasn't the original reason Toyota was doing it, Ford is now using this as well and I expect we'll see others follow suit.

There are two schools of thought about IVD's:
1. That volatile compounds (so, not VII's) like lighter fractions from the base oil blend, flash off and make their way into the intake tract through the PCV, ultimately forming deposits on the back of the valves.
2. That oil mists produced during operation make their way through the same plumbing and the various components of these mists produce deposits.

The rationale behind focusing on Noack is #1, with #2, you accept that oil will be introduced into the intake regardless and are looking at reducing the concentration of the components that seem most inclined to form deposits.

This strikes me as akin to trying to use 10W-60 to delay rod bearing failure. It's still going to happen, but maybe it happens a bit slower.

One of the biggest drivers of volatilized compounds, and probably the mist angle too, would be fuel dilution, which varies considerably between marques and engine designs. If >5% of your sump is gasoline, clearly, that's going to present as a far greater propensity for volatilized compounds to flash off and get introduced to the intake tract via the PCV.
I would agree with you. I would also say that I would not agree that there is any significant recent changes in raw materials to support the original post. There is certainly no disadvantage to formulate with low volatility in mind. IVD's are the totality of everything allowed to reach a non fuel wetted valve. Keeping the oil in the pan is the goal. Keeping the engine clean has a lot of merit as well.
 





Thanks for your service - both here and in the military !
 
... There are two schools of thought about IVD's:
1. That volatile compounds (so, not VII's) like lighter fractions from the base oil blend, flash off and make their way into the intake tract through the PCV, ultimately forming deposits on the back of the valves.
2. That oil mists produced during operation make their way through the same plumbing and the various components of these mists produce deposits.

The rationale behind focusing on Noack is #1, with #2, you accept that oil will be introduced into the intake regardless and are looking at reducing the concentration of the components that seem most inclined to form deposits. ...
Somewhere, maybe BitOG, I read of a study demonstrating that your #2 predominates. It may have been done by Nissan, as I recall. Evidence included that oil reaching the intake included substantially the same concentrations of additives as the oil in the pan (whereas volatilized base oil would not). Sorry, I didn't save a link.
 
I would agree with you. I would also say that I would not agree that there is any significant recent changes in raw materials to support the original post. There is certainly no disadvantage to formulate with low volatility in mind. IVD's are the totality of everything allowed to reach a non fuel wetted valve. Keeping the oil in the pan is the goal. Keeping the engine clean has a lot of merit as well.
Dave, is volatility the only attribute that keeps oil in the pan, or are there other ways besides oil formulations to do this? Meaning, have you seen or experienced any testing showing that windage pans, or crank scrapers, or vacuum pumps, or pan-e-vacs have beneficial impacts as well? I know these mechanical “fixes” can’t impact OEM engines, but wondering for people who modify their engines- yes, oil itself has an impact; but do certain practices have a greater impact on aftermarket improvements? If one is willing to do X or Y, does it synergistically pair with improvements in oil composition & volatility?

I get that this may be outside the scope of an “oil-only” improvement, but if we’re chasing the elimination of IVDs I think they’re valid questions… thanks!
 
From tailpipe of '18 Accent . March of '19 . Less than 6,000 on engine . So much for air quality . 😷

View attachment 132812
In 2020 they switched to dual port injection. All my previous GDI vehicles before this Accent had tailpipe soot like what's on your fingers. So far, the Palisade has surprised me with very little soot. Fingers crossed.
 
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